1. Field of the Invention
The invention relates to a transfer press and a method of driving slides thereof, and more particularly, to a transfer press, in which a plurality of slides are provided, and a method of driving slides used in the transfer press, or to a transfer press, in which a plurality of units each composed of a crown, slide and a bed are arranged linearly and uprights are provided between adjacent units to be common thereto, and a method of driving slides used in the transfer press.
2. Description of the Related Art
Conventionally, a transfer press has been known, in which slides conformed to at least one working station. Such transfer press is frequently used in the case where stations are large in number, the case where workpieces are large in size, the case where an overall pressing force is great, or the case where a blanking station is provided for use of a coiled stock.
In such transfer press, respective slides are driven substantially at the same time by one main motor common to all the slides. Also, provided in the transfer press are a set of a flywheel rotated constantly by the main motor, a clutch for intermittently transmitting energy of the flywheel to the respective slides, and a brake for stoppage of movements of the slides, in addition to the main motor.
Also, in recent years, a transfer press has been known, in which units each composed of a set of a crown, slide and a bed are modularized and uprights are provided between adjacent units to be common thereto. In this transfer press, combination of the modularized units in accordance with the specification of the press enables achieving an improvement in use for various purposes, which is achieved by diversification in need and easiness in modification of specification, cost reduction and an improvement in property of transportation.
In such transfer press, slides in the respective units are also driven substantially at the same time by one main motor common to all the units. Also, provided in transfer press are a set of a flywheel rotated constantly by a main motor, a clutch for intermittently transmitting energy of the flywheel to the respective slides, and a brake for stoppage of movements of the slides, in addition to the main motor.
In the above-mentioned transfer press, however, all the slides are driven at the same time by one main motor, so that the main motor is made large in size and the flywheel, clutch and the brake are also made large in size. Accordingly, there is caused a problem that purchasing of these parts involves much labor and high cost, for example, production is impeded because the transfer press cannot but be stopped for a long period of time in the case where these parts must be exchanged in a transfer press actually in use.
Also, since all the slides in the transfer press are driven substantially at the same time without phase difference, restrictions are imposed on manufacture of metallic molds and configuration of workpieces, thus causing a problem that various workings cannot be accommodated.
It is an object of the invention to provide a transfer press, in which it is possible to reduce the size of drive means for driving slides and to realize various workings, and a method of driving slides thereof.
A transfer press according to a first aspect of the invention is provided with a plurality of slides, and comprises slide drives being drive sources provided every slide, and control means for controlling the slide drives to synchronously drive and/or singly drive the slides individually.
In the transfer press provided with a plurality of slides, according to the first aspect of the invention, the slide drives containing drive sources are provided every slide, and so the drive source suffices to drive one slide and has no need of so large capacity as that in the prior art, by which considerably small-sized drive sources used for various purposes can be used to reduce labor and cost required for purchasing.
Also, the respective slides are driven in various modes by controlling the slide drives provided every slide.
For example, in addition to the case where the respective slides are driven at the same time as in the prior art (synchronously drive without phase difference), the slides can be synchronously driven with optional phase difference, or stopped a predetermined time every cycle at a top dead point, or singly driven individually. Accordingly, one press can perform working in a tandem press and a single press as well as working of a transfer press, whereby various workings can be accommodated. The above-mentioned object can be attained as described above.
A transfer press according to a second aspect of the invention is one, in which a plurality of units each composed of a crown, a slide and a bed are arranged along a workpiece transfer direction and uprights are provided between adjacent units to be common thereto, and which comprises slide drives being drive sources provided every slide; and control means for controlling the slide drives to synchronously drive and/or singly drive the slides individually.
According to the second aspect of the invention, the slide drives are provided every unit, and so the drive source constituting the slide drive suffices to drive a slide in one unit, by which considerably small-sized drive sources used for various purposes can be used to reduce labor and cost required for purchasing as described with respect to the first aspect of the invention.
Also, control of the slide drives with the control means enables the slides to be synchronously driven with optional phase difference, or stopped a predetermined time every cycle at a top dead point, or singly driven individually, in addition to the case where the slides provided every unit are driven at the same time as in the prior art (synchronously drive without phase difference). Accordingly, by driving the slides with phase differences, which are conformed to levels, at which workpieces are worked, dimensions of metallic molds or the like, or singly driving the slides, one press can achieve working in a tandem press and a single press as well as working of a transfer press, whereby various workings can be accommodated. The above-mentioned object can be attained as described above.
A method of driving slides of a transfer press provided with a plurality of slides, according to a third aspect of the invention, comprises the steps of driving the slides by means of drive sources provided every slide, and controlling slide drives, which include the drive sources, to synchronously drive and/or singly drive the slides individually.
The third aspect of the invention provides a slide driving method that can be realized by means of the transfer press of the first aspect of the invention, and therefore attains the object of the invention as described with respect to the first aspect of the invention. In addition, included in the invention are the case where all the plurality of slides are synchronously driven without phase difference, the case where all the plurality of slides are synchronously driven with predetermined phase differences, the case where all the plurality of slides are singly driven, and the case where synchronous drive without phase difference, synchronous drive with phase difference, synchronous drive, in which the slides are stopped a predetermined time every cycle at a top dead point, and single drive are combined optionally, the single drive including the case where the slides are maintained in stoppage.
A method of driving slides of a transfer press, in which a plurality of units each composed of a crown, a slide and a bed are arranged along a workpiece transfer direction and uprights are provided between adjacent units to be common thereto, according to the third aspect of the invention, comprises the steps of driving the slides by means of drive sources provided every slide, and controlling slide drives, which include the drive sources, to synchronously drive and/or singly drive the slides individually.
The fourth aspect of the invention of provides a slide driving method that can be realized by means of the transfer press of the second aspect of the invention, and therefore attains the object of the invention as described with respect to the second aspect of the invention of. In addition, included in the invention are the case where all the plurality of slides are synchronously driven without phase difference, the case where all the plurality of slides are synchronously driven with predetermined phase differences, the case where all the plurality of slides are singly driven, and the case where synchronous drive without phase difference, synchronous drive with phase difference, synchronous drive, in which the slides are stopped a predetermined time every cycle at a top dead point, and single drive are combined optionally, the single drive including the case where the slides are maintained in stoppage.
A method of driving slides of a transfer press, according to the fifth aspect of the invention, is one according to the third or fourth aspect of the invention, wherein when at least a pair of slides are to be synchronously driven, the slide drives are controlled so that at least a slide is synchronously driven while stopping a predetermined time every cycle at a top dead point.
In such method, it is possible to make a transfer press function as a tandem press, and since idle stations are not necessarily required between the working stations, a space for installation is small and productivity is high.
A method of driving slides of a transfer press, according to a sixth and seventh aspect the invention, is one according to any one of the third through fifth aspects of the invention, where in the case where at least a pair of slides are to be synchronously driven, the slide drives are controlled so that the slides are synchronously driven with phase difference.
In such method, in the case where one slide is driven earlier in phase than the other slides, the one slide has been terminated in working to be returned to a higher level when working in the other slides is terminated. Accordingly, even a workpiece having a larger height of working can be surely transferred in the working station, in which the one slide is present, without interference between the workpiece and a metallic mold.
Also, when phase difference is optionally set in all the units, the transfer press will function as a tandem press, and use of the press for various purposes is surely promoted.
A method of driving slides of a transfer press, according to the invention of any one of seventh through eleventh aspects of the invention, is one according to any one of the third through sixth aspects of the invention, wherein other slides are driven in a state, in which any one slide is stopped.
Such method makes it possible for a transfer press to function as a single press, and stoppage of slides not in use reduces load, for which the slides must be driven, and energy consumption in the slide drives to lead to economy.
A method of driving slides of a transfer press, according to the invention of any one of the 12th through 15th aspects of the invention is one according to any one of the third through seventh aspects of the invention, wherein other slides are driven in a state, in which any one slide is stopped and the drive source therefor is stopped.
A slide can be maintained in stoppage by releasing a clutch so as to prevent energy of a rotating flywheel from being transmitted to the slide side and causing a brake to hold the slide, in which case energy for rotating the flywheel with the use of a drive source is consumed to lead to want of economy.
In contrast, the invention is economical because the drive source is also stopped to eliminate wasteful energy consumption.
Respective embodiments of the invention will be described below with reference to the drawings.
In addition, the same constituent members in second to fourth embodiments described later as those in a first embodiment and constituent members having the same function in the second to fourth embodiments as that of the constituent members in the first embodiment are denoted by the same characters as those in the first embodiment, and an explanation therefor is omitted.